Bronchoalveolar Fluid Samples Research Articles

A Multi-dimensional Review on Severe Acute Respiratory Syndrome Coronavirus-2.

The advent and spread of novel coronavirus (nCoV) has posed a new public health crisis since December 2019. Several cases of unexplained pneumonia occurred in Wuhan, Hubei Province, China, only a month before the Chinese Spring festival. After the diagnosis of bronchoalveolar fluid samples of people infected, the new coronavirus was identified using nextgeneration sequence technology. This work aims to provide information regarding COVID-19 that will help the researchers to identify the vital therapeutic targets for SARS-CoV-2 and also will provide insights into some significant findings of recent times highlighted by scientific communities around the globe. In this review, we have tried to explore multiple aspects related to COVID-19, including epidemiology, etiology, COVID-19 variants, vaccine candidates, potential therapeutic targets, the role of natural products, and computational studies in drug design and development, repurposing, and analysis of crystal structures available for COVID-19 related protein structures. Druggable targets include all viral enzymes and proteins involved in viral replication and regulation of host cellular machines. The medical community tracks several therapies to combat the infection by investigating various antiviral and immunomodulatory mechanisms. While some vaccines are approved in this worldwide health crisis, a more precise therapy or drug is formally recommended to be used against SARS-CoV-2 infection. Natural products other than synthetic drugs have been tested by in silico analysis against COVID-19. However, important issues still need to be addressed regarding in vivo bioavailability and better efficacy.

COVID-19 Pnömonili Hastaların Solunum Yolu Örneklerinde Sekonder Bakteriyel Ajanlar ve Antibiyotik Direnç Profilleri

Objective: To assess secondary bacterial pneumonia agents and antibiotic resistance rates in patients with COVID-19 pneumonia and to compare findings with the pre-pandemic period. Materials and Methods: Bacteria grown in endotracheal aspirate fluid and bronchoalveolar fluid samples of patients diagnosed with COVID-19 between January 2020 and December 2020, and antibiotic resistance rates were retrospectively compared with samples of the year before the pandemic. Isolates were identified at the species level with an automated system (VITEK 2, bioMérieux, France), and antimicrobial susceptibility was determined according to EUCAST criteria. Results: A total of 900 culture results were examined in 2019. Acinetobacter baumannii was detected in 36%, Klebsiella pneumoniae in 23%, Pseudomonas aeruginosa in 14%, and Staphylococcus aureus in 8%. In 2020, 660 culture results were examined, and the same bacteria were detected in 43%, 23%, 16%, and 5%, respectively. K. pneumoniae's resistance to third-generation cephalosporins, and A. baumannii's resistance to gentamycin and tobramycin, were found to have increased significantly during the pandemic period. Conclusions: The growth of multidrug-resistant Gram-negative bacteria was frequently detected in respiratory secretions obtained during the COVID-19 pandemic. Regional bacterial agents and antibiotic resistance profiles should be clarified, and empirical therapy should be selected accordingly in COVID-19.

Screening for differentially expressed microRNAs in BALF and blood samples of infected COVID-19 ARDS patients by small RNA deep sequencing.

BackgroundThe pandemic COVID‐19 has caused a high mortality rate and poses a significant threat to the population of the entire world. Due to the novelty of this disease, the pathogenic mechanism of the disease and the host cell's response are not yet fully known, so lack of evidence prevents a definitive conclusion about treatment strategies. The current study employed a small RNA deep‐sequencing approach for screening differentially expressed microRNA (miRNA) in blood and bronchoalveolar fluid (BALF) samples of acute respiratory distress syndrome (ARDS) patients.MethodsIn this study, BALF and blood samples were taken from patients with ARDS (n = 5). Control samples were those with suspected lung cancer candidates for lung biopsy (n = 3). Illumina high‐throughput (HiSeq 2000) sequencing was performed to identify known and novel miRNAs differentially expressed in the blood and BALFs of ARDS patients compared with controls.ResultsResults showed 2234 and 8324 miRNAs were differentially expressed in blood and BALF samples, respectively. In BALF samples, miR‐282, miR‐15‐5p, miR‐4485‐3p, miR‐483‐3p, miR‐6891‐5p, miR‐200c, miR‐4463, miR‐483‐5p, and miR‐98‐5p were upregulated and miR‐15a‐5p, miR‐548c‐5p, miR‐548d‐3p, miR‐365a‐3p, miR‐3939, miR‐514‐b‐5p, miR‐513a‐3p, miR‐513a‐5p, miR‐664a‐3p, and miR‐766‐3p were downregulated. On the contrary, in blood samples miR‐15b‐5p, miR‐18a‐3p, miR‐486‐3p, miR‐486‐5p, miR‐146a‐5p, miR‐16‐2‐3p, miR‐6501‐5p, miR‐365‐3p, miR‐618, and miR‐623 were top upregulated miRNAs and miR‐21‐5p, miR‐142a‐3p, miR‐181‐a, miR‐31‐5p, miR‐99‐5p, miR‐342‐5p, miR‐183‐5p, miR‐627‐5p, and miR‐144‐3p were downregulated miRNAs. Network functional analysis for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), in ARDS patients' blood and BALF samples, showed that the target genes were more involved in activating inflammatory and apoptosis process.ConclusionBased on our results, the transcriptome profile of ARDS patients would be a valuable source for understanding molecular mechanisms of host response and developing clinical guidance on anti‐inflammatory medication.

Sandwich-type homogeneous chemiluminescence immunoassay based on nanoparticle toward detection of Aspergillus galactomannan antigen

Aspergillus species continue to be an important cause of life-threatening infection in immunocompromised patients and galactomannan (GM) is a popular biomarker in the diagnosis of invasive aspergillosis (IA). Here we developed and validated an amplified luminescent proximity homogenous assay-linked immunosorbent assay (AlphaLISA) for serum and bronchoalveolar fluid (BALF) GM based on this approach. Technological processes and reaction conditions were optimized. Study assessments included reproducibility, accuracy, stability, and cross reactivity experiments. Method comparisons with the commercial Platelia Aspergillus enzyme immunoassay (Bio-Rad Laboratories) were performed using 201 clinical serum and BALF samples. Under the optimized conditions, the total runtime of the AlphaLISA method was 40 min with simple operation. The percent coefficient variations (CVs%) were lower than 15%, and the recoveries were in the range of 90–110%. Of note, the proposed assay exhibited acceptable stability and did not display cross-reactivity with non-Aspergillus pathogens. Compared with the results from the Platelia kit, there was a satisfied overall qualitative agreement of 97.5% and overall quantitative correlation coefficient of 0.59. In all, we have successfully developed an alternative novel homogeneous nanoparticle-based immunoassay, which has shorter incubation time and easier protocol than the ones of conventional ELISA. It could serve as an alternative to the well-established Platelia assay for measurement of GM in serum and BALF.

Lung microbiota features of stage III and IV non-small cell lung cancer patients without lung infection.

BackgroundThe microbial community affects the occurrence, development, metastasis and treatment response of cancers. But the detailed role and characteristics of lung microbiota (LM) in non-small cell lung cancer (NSCLC) are not fully known. For NSCLC associated microbiota analysis, it is valuable to combine multiple levels of detection, e.g., tumor, blood plasma, and bronchoalveolar fluid (BALF), but not single tissues.MethodsThis study collected above three sample types from NSCLC patients free from lung infection and aimed to describe their LM features using sequencing techniques. All patients diagnosed at the Department of Oncology in Shijiazhuang People’s Hospital with stage III or IV NSCLC from May 2019 to April 2020 were enrolled. All 37 pieces of tumor tissues and 6 blood samples were sent for pathogen targeted sequencing; for the BALF samples, 4 were used for pathogen targeted sequencing and 2 were sent for 16S ribosomal DNA (rDNA) sequencing.ResultsWe detected 49 pathogenic microorganisms (PMs) in the 37 tumor samples, 28 PMs in the 4 BALF samples, and 14 PMs in the 6 plasma samples. Overall, there were 5 common PMs in 3 types of samples. Between the tumor and BALF samples, there were another 11 common elements. In the 5 tumor-plasma pairs, the presence of a specific PM in blood was not necessarily consistent with that in the tumor. In the tumor-BALF pairs, the PM diversity was dramatically higher in the BALF than in the tumor. The PMs detected in the BALF could largely cover the PMs in the tumor. In the BALF 16S rDNA sequencing, there were 82 common operational taxonomic units (OTUs), and the microbiota in the BALF of advanced NSCLC patients exhibited some similarity.ConclusionsThis study showed the unique features of LM. The amount of intra-tumoral PMs was not necessarily consistent with that in the blood, but there was an obvious correlation between the intra-tumoral microbiota and that in the BALF. It is convenient and non-invasive to obtain BALF. Detection of LM classification and abundance in the BALF may help evaluate the severity of NSCLC.

Development of a Droplet Digital Polymerase Chain Reaction for Sensitive Detection of Pneumocystis jirovecii in Respiratory Tract Specimens.

Background: Pneumocystis jirovecii is a human-specific opportunistic fungus that causes Pneumocystis pneumonia (PCP), a life-threatening opportunistic lung infection that affects immunocompromised patients. P. jirovecii colonization may be linked to the transmission of the infection. The detection of P. jirovecii in immunocompromised patients is thus especially important. The low fungal load and the presence of PCR inhibitors limit the usefulness of quantitative PCR (qPCR) for accurate absolute quantification of P. jirovecii in specimens. Droplet digital PCR (ddPCR), however, presents a methodology that allows higher sensitivity and accuracy. Here, we developed a ddPCR method for detecting P. jirovecii DNA in respiratory specimens, and evaluated its sensitivity against qPCR.Materials and Methods: One bronchoalveolar fluid (BALF) sample each was collected from 82 patients with potential PCP to test the presence of P. jirovecii DNA using both ddPCR and qPCR, and samples with inconsistent results between the two methods were further tested by metagenomic next generation sequencing (mNGS). In addition, 37 sputum samples from 16 patients diagnosed with PCP, as well as continuous respiratory tract specimens from nine patients with PCP and treated with sulfonamides, were also collected for P. jirovecii DNA testing using both ddPCR and qPCR.Results: ddPCR and qPCR gave the same results for 95.12% (78/82) of the BALF samples. The remaining four specimens tested positive using ddPCR but negative using qPCR, and they were found to be positive by mNGS. Detection results of 78.37% (29/37) sputum samples were consistent between ddPCR and qPCR, while the other eight samples tested positive using ddPCR but negative using qPCR. The P. jirovecii load of patients with PCP decreased to undetectable levels after treatment according to qPCR, but P. jirovecii was still detectable using ddPCR.Conclusions: ddPCR was more sensitive than qPCR, especially at detecting low-pathogen-load P. jirovecii. Thus, ddPCR represents a useful, viable, and reliable alternative to qPCR in P. jirovecii testing in patients with immunodeficiency.

Detection of Cytokines and Collectins in Bronchoalveolar Fluid Samples of Patients Infected with Histoplasma capsulatum and Pneumocystis jirovecii.

Histoplasmosis and pneumocystosis co-infections have been reported mainly in immunocompromised humans and in wild animals. The immunological response to each fungal infection has been described primarily using animal models; however, the host response to concomitant infection is unknown. The present work aimed to evaluate the pulmonary immunological response of patients with pneumonia caused either by Histoplasma capsulatum, Pneumocystis jirovecii, or their co-infection. We analyzed the pulmonary collectin and cytokine patterns of 131 bronchoalveolar lavage samples, which included HIV and non-HIV patients infected with H. capsulatum, P. jirovecii, or both fungi, as well as healthy volunteers and HIV patients without the studied fungal infections. Our results showed an increased production of the surfactant protein-A (SP-A) in non-HIV patients with H. capsulatum infection, contrasting with HIV patients (p < 0.05). Significant differences in median values of SP-A, IL-1β, TNF-α, IFN-γ, IL-18, IL-17A, IL-33, IL-13, and CXCL8 were found among all the groups studied, suggesting that these cytokines play a role in the local inflammatory processes of histoplasmosis and pneumocystosis. Interestingly, non-HIV patients with co-infection and pneumocystosis alone showed lower levels of SP-A, IL-1β, TNF-α, IFN-γ, IL-18, IL-17A, and IL-23 than histoplasmosis patients, suggesting an immunomodulatory ability of P. jirovecii over H. capsulatum response.

Neutrophils and secondary infections in COVID-19 induced acute respiratory distress syndrome

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus is the cause of the current global pandemic and has affected more than 188 countries worldwide. Infection by the virus can have diverse clinical manifestations, with one of the most severe clinical manifestation being respiratory failure and the development of acute respiratory distress syndrome. Clinical manifestations of acute respiratory distress syndrome secondary to SARS-CoV-2 are also diverse with a lack of diagnostic tools to distinguish between primary viral infection and secondary bacterial infections. This was a single-centre, retrospective case-control study of bronchoalveolar lavage fluid cell counts, flow cytometry and culture results from mechanically ventilated patients with SARS-CoV-2 (COVID-19) pneumonia and acute respiratory distress syndrome. Neutrophils were the predominant cell type in bronchoalveolar fluid samples up to 2 weeks into mechanical ventilation. There also was a strong correlation between positive respiratory cultures and significant elevation in bronchoalveolar fluid neutrophil counts/percentages and serum C-reactive protein levels. Absolute levels of T cell subtypes correlated with reduced lung compliance measurements. Patients with SARS-CoV-2 and severe respiratory disease are at risk for secondary infections. In some COVID-19 patients, serum C-reactive protein and bronchoalveolar fluid neutrophils may be correlated with a secondary infection.

Association of CCL7 Promoter Polymorphism with Responsiveness to Allergen in Cynomolgus Macaque Model of Asthma

BACKGROUND: C-C motif Ligand 7 (CCL7) has been reported to be associated with asthma severity in humans. Cynomolgus macaques (Macaca fascicularis; Mf) are often used as animal model of asthma but little is known about Mf genetic profile such as polymorphism. Our aim was to identify CCL7 polymorphism in Mf as a potential surrogate marker for identification of allergen responsiveness in the Mf model of asthma.METHODS: Real-time PCR was performed on archive of bronchoalveolar fluid samples previously collected from Mf that were exposed to allergen. Expression of CCL7 mRNA was evaluated, and sequencing technique was used to identify polymorphism in this gene.RESULTS: The results showed that CCL7 expression did not differ between Mf, despite a trend of lower expression in Mf that exhibited high response to allergen. By direct DNA sequencing of CCL7, 10 sequence variants were identified; three in promoter region (-460 G/A, -459 A/G, -456 -/A ), two in exon 1 (9 A/G, 65 G/C), four in intron 1 (135 T/C, 254 T/C, 420 T/C, 453 A/G), and one in intron 2 (1205 T/A).CONCLUSION: There was an association between Mf sensitivity to allergen with CCL7 promoter polymorphism at (-456 -/A). These results suggest that CCL7 may be a potential genetic marker to identify Mf sensitivity to allergen, which could be a useful tool to efficiently select for Mf model of asthma.KEYWORDS: asthma, CCL7, allergy, Ascaris suum, nonhuman primate

4029 Stromelysin-1 as a biomarker for acute lung injury

OBJECTIVES/GOALS: Acute lung Injury (ALI) has long been considered a proceeding event to the development of Acute Respiratory Distress Syndrome (ARDS). Diagnosis of classical ALI and ARDS remains difficult relies on clinical components of the Berlin Criteria, interpretation of radiographs and exclusion of pulmonary edema inducing processes. The precipitating factor for developing ALI involves direct or indirect insult to the lungs. Recent studies have described metalloproteinase-3 (MMP3) to be elevated in plasma samples of patients with lung injury and potentially affected by tobacco use. MMP3 can degrade extracellular matrix components contributing to lung edema and inflammation. This study was conducted to examine the utility of matrix metalloproteinase-3 (MMP3) as a biomarker of lung injury. METHODS/STUDY POPULATION: We conducted a single center, retrospective cohort study of patients admitted to the medical ICU (MICU). De-identified bronchoalveolar fluid (BALF) samples were collected and stored at −80C. Enzymatic activity of MMP3 was determined using a fluorescent resonance energy transfer (FRET) assay. Demographics, comorbidities, evidence of lung injury and patient outcomes were collected. Data were reported with descriptive statistics and data was analyzed with t-tests for statistical significance. RESULTS/ANTICIPATED RESULTS: 55 patient BALF samples were included in the final analysis (mean age 58 +/-17, 58.2% male). 54.5% (n = 30) of patients were determined to have lung injury, 29% (n = 16) of patients had COPD and 45.5% (n = 25) of patients were smokers. MMP3 was higher in patients with lung injury (2363 vs 1052 maxV; p = 0.008). Smoking was associated with decreased MMP3 activity (1231 vs. 2215; p = 0.048). COPD was not associated with differences in MMP3 (1563 vs. 1852; p = 0.605). DISCUSSION/SIGNIFICANCE OF IMPACT: Lung Injury results in elevated MMP3 levels. Smoking was not shown to increase MMP3 levels and may in fact increase them. COPD demonstrated no effect on MMP3 levels. MMP3 levels may vary based on the mode of lung injury (i.e. direct vs indirect) and smoking may impact the activity of the enzyme. Further research should assess activity of MMP3 through different modes of lung injury.

Clinical, virological and immunological features from patients infected with re-emergent avian-origin human H7N9 influenza disease of varying severity in Guangdong province.

BackgroundThe second wave of avian influenza H7N9 virus outbreak in humans spread to the Guangdong province of China by August of 2013 and this virus is now endemic in poultry in this region.MethodsFive patients with H7N9 virus infection admitted to our hospital during August 2013 to February 2014 were intensively investigated. Viral load in the respiratory tract was determined by quantitative polymerase chain reaction (Q-PCR) and cytokine levels were measured by bead-based flow cytometery.ResultsFour patients survived and one died. Viral load in different clinical specimens was correlated with cytokine levels in plasma and broncho-alveolar fluid (BALF), therapeutic modalities used and clinical outcome. Intravenous zanamivir appeared to be better than peramivir as salvage therapy in patients who failed to respond to oseltamivir. Higher and more prolonged viral load was found in the sputum or endotracheal aspirates compared to throat swabs. Upregulation of proinflammatory cytokines IP-10, MCP-1, MIG, MIP-1α/β, IL-1β and IL-8 was found in the plasma and BALF samples. The levels of cytokines in the plasma and viral load were correlated with disease severity. Reactivation of herpes simplex virus type 1(HSV-1) was found in three out of five patients (60%).ConclusionExpectorated sputum or endotracheal aspirate specimens are preferable to throat swabs for detecting and monitoring H7N9 virus. Severity of the disease was correlated to the viral load in the respiratory tract as well as the extents of cytokinemia. Reactivation of HSV-1 may contribute to clinical outcome.

Pneumocytis jiroveci Infection Developed in Aplastic Anemia Patients Under Prophylaxis

Pneumocystis jiroveci (PJ) is an opportunistic pathogen that can cause infection in immunocompromised patients, primarily in patients with AIDS (Acquired Immune deficiency syndrome). It is quite rare in healthy induviduals. It causes interstitial pneumonia, severe hypoxemia and may demonstrate a fulminant course. Trimethoprim- sulfamethoxazole (TMP-SMX) prophylaxis is recommended for risky patients. In this article, we present a patient with the diagnosis of aplastic anemia who developed pneumocystis jiroveji pneumonia (PJP) and scheduled for haploidentical bone marrow transplantation (BMT) from mother. The patient was under TMP-SMX prophylaxis for a long time and had no history of hospitalization except for the need for transfusion. He was admitted to the emergency department with sudden onset of respiratory distress, and during follow- up period he required mechanical ventilation due to hypoxia and rapid clinical deterioration. Bronchoalveolar fluid samples obtained showed the presence of Pneumocystis jirovecii. Clinical improvement was achieved with mechanical ventilation and supportive treatment. Colonization under antibiotic prophylaxis suggests that effectiveness of prophylaxis does not always prevent colonization.&nbsp;

Detection of herpesvirus EBV DNA in the lower respiratory tract of ICU patients: a marker of infection of the lower respiratory tract?

Epstein-Barr virus (EBV) is a lymphotropic herpesvirus causing clinically self-limiting but lifelong persisting infections. Although several severe diseases (e.g., Hodgkin's disease) are associated with EBV, its role in lower respiratory tract infections is still elusive. The prevalence of EBV, herpes simplex virus (HSV) and cytomegalovirus (CMV) in bronchoalveolar fluid (BAL) samples was evaluated in a retrospective study. BAL samples from 135 patients in the intensive or coronary care unit (ICU/ICC) at University Hospital Frankfurt/Main (Germany) were investigated using an in-house real-time PCR to detect EBV-, HSV- and CMV-specific DNA. Overall, herpesvirus DNA was detected in n=82/135 BAL samples (60.7%). Besides mono-infections with either EBV or HSV, concomitant infection with EBV and HSV DNA was most frequent, whereby the relative HSV viral load was typically higher. Patients with HSV-positive BAL required mechanical ventilation on average 5days longer than patients with HSV-negative BAL (p=0.006). Additionally, the proinflammatory cytokine IL-6 was significantly elevated in sera of patients positive for EBV in comparison with patients with EBV-negative BAL (p=0.01). This study demonstrates a high prevalence of herpesviruses in BAL samples of ICU/ICC patients. The detection of one or more herpesvirus in BAL is strongly associated with the duration of ventilation and patient's age. The association between IL-6 levels and EBV detection should be evaluated in further studies.

Stromal cells can be cultured and characterized from diagnostic bronchoalveolar fluid samples obtained from patients with various types of interstitial lung diseases.

Increased proliferation of stromal cells is a typical feature encountered in several lung diseases. The objective of this study was to evaluate the success of standardized process for culturing stromal cells from small volumes of diagnostic bronchoalveolar lavage (BAL) fluid samples collected from various patients and to characterize the cultured cells. Small volumes (average 15 mL) of BAL fluid samples were collected from 98 patients who underwent bronchoscopy and BAL for diagnostic purposes. The cells were cultured in vitro and characterized by immunohistochemistry, electron microscopy, flow cytometry and differentiation tests. Cells could be cultured from 62% of samples with the success rate varying with the disease (p = 0.003). Cultures from samples of the patients with idiopathic pulmonary fibrosis, non-specific interstitial pneumonia, connective tissue disorder associated interstitial lung disease and allergic alveolitis had a higher success rate than samples derived from control lung (p < 0.001, 0.03, 0.03 and 0.044, respectively). Smokers had a higher success rate compared with non-smokers (p = 0.035). The cultured cells were fibroblasts or myofibroblasts, but shared also similarities with progenitor-type cells. The study shows that mesenchymal cells can be cultured and studied from small volumes of diagnostic BAL fluid samples from patients with several different types of lung diseases.

Aspiration, Localized Pulmonary Inflammation, and Predictors of Early-Onset Bronchiolitis Obliterans Syndrome after Lung Transplantation

We hypothesized that immune mediator concentrations in the bronchoalveolar fluid (BALF) are predictive of bronchiolitis obliterans syndrome (BOS) and demonstrate specific patterns of dysregulation, depending on the presence of acute cellular rejection, BOS, aspiration, and timing of lung transplantation. We prospectively collected 257 BALF samples from 105 lung transplant recipients. The BALF samples were assessed for absolute and differential white blood cell counts and 34proteins implicated in pulmonary immunity, inflammation, fibrosis, and aspiration. There were elevated BALF concentrations of interleukin (IL)-15, IL-17, basic fibroblast growth factor, tumor necrosis factor-α, and myeloperoxidase, and reduced concentrations of α1-antitrypsin, which were predictive of early-onset BOS. Patients with BOS had an increased percentage of BALF lymphocytes and neutrophils, with a reduced percentage of macrophages (p < 0.05). The BALF concentrations of IL-1β; IL-8; interferon-γ-induced protein 10; regulated upon activation, normal T-cell expressed and secreted; neutrophil elastase; and pepsin were higher in patients with BOS (p < 0.05). Among those with BOS, BALF concentrations of IL-1RA; IL-8; eotaxin; interferon-γ-induced protein 10; regulated upon activation, normal T-cell expressed and secreted; myeloperoxidase; and neutrophil elastase were positively correlated with time since transplantation (p < 0.01). Those with worse grades of acute cellular rejection had an increased percentage of lymphocytes in their BALF (p< 0.0001) and reduced BALF concentrations of IL-1β, IL-7, IL-9, IL-12, granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, interferon-γ, and vascular endothelial growth factor (p ≤ 0.001). Patients with aspiration based on detectable pepsin had increased percentage of neutrophils (p < 0.001) and reduced BALF concentrations of IL-12 (p < 0.001). The BALF levels of IL-15, IL-17, basic fibroblast growth factor, tumor necrosis factor-α, myeloperoxidase, and α1-antitrypsin at 6 to 12 months after lung transplantation are predictive of early-onset BOS, and those with BOS and aspiration have an augmented chemotactic and inflammatory balance of pulmonary leukocytes and immune mediators. These data justify the surgical prevention of aspiration and argue for the refinement of antirejection regimens.

Disposition of linezolid in the isolated rat lung after systemic and pulmonary drug delivery

To characterize the distribution of linezolid in lung when it accesses this organ from the systemic circulation and when administered through the pulmonary route and to evaluate the influence of the 'respiratory mode' in the pulmonary distribution for both routes. The study was conducted with 24 Wistar rats divided into four groups treated with linezolid under different experimental conditions. After the animals had been subjected to a tracheotomy followed by mechanical ventilation, the lungs were isolated. After a 5 min stabilization period, the antibiotic was administered through the systemic or the pulmonary route and samples of efferent fluid (EF) were collected using a previously programmed fraction collector. Samples of bronchoalveolar fluid (BALF) and of lung tissue were also taken at the end of each experiment. The concentrations of linezolid in the samples were determined using an HPLC technique with UV detection. The administration of linezolid through the inhalatory route significantly increased the levels of the drug in lung tissue and BALF with lung tissue/EF partition coefficients of 8.33 +/- 2.51 as compared with 1.90 +/- 0.78 for systemic administration. Also, the decrease in respiratory rate together with the increase in tidal volume favoured the process of linezolid distribution in pulmonary tissues and fluids. Administration through the pulmonary route affords and excellent method for passively vectoring linezolid to the pulmonary fluids and tissues and the respiratory mode seems to affect the disposition of the antibiotic in this tissue for both administration routes.

Fatal pulmonary infection in a leukaemic patient caused by Hormographiella aspergillata

A case of autopsy-proven fungal pneumonia in a relapsed leukaemia patient is reported. The fungus Hormographiella aspergillata was cultured from two bronchoalveolar fluid samples and identified through morphological examination and ITS2 sequence analysis. In addition, galactomannan was detected in eight consecutive serum samples, which suggested a co-infection with Aspergillus species. The patient was treated with caspofungin.

Isolation and culture of human macrophages.

Methods to isolate and culture human monocyte-derived macrophages and alveolar macrophages are described. Monocytes are obtained from buffy-coat preparations by Ficoll density gradient centrifugation, followed by adhesion-mediated purification on tissue culture or gelatin-coated plastic. The monocytes differentiate into macrophages in vitro by culturing in medium containing autologous human fibrin-depleted plasma. Alveolar macrophages can be purified from bronchoalveolar fluid samples by adhesion to tissue culture plastic. If resected lung tissue is available, alveolar macrophages can be obtained by mechanically disrupting the lung parenchyma, followed by adhesion-mediated purification.

Pneumocystis jirovecii dihydropteroate synthase genotypes in French patients with pneumocystosis: a 1998-2001 prospective study.

Dihydropteroate synthase gene (DHPS) mutations at codons 55 and 57 have been associated with sulfa/sulfone resistance in Pneumocystis jirovecii strains from patients who previously received prophylaxis. To evaluate the prevalence of these mutations, a portion of P. jirovecii DHPS gene was analysed using PCR combined with restriction fragment length polymorphism (RFLP) analysis in 92 bronchoalveolar fluid samples collected between January 1998 and September 2001 from French patients with pulmonary pneumocystosis (PCP). Seventy-six samples contained the wild-type DHPS genotype (82.6%) and 16 contained a mutant genotype (17.4%). Twelve out of the 16 isolates with a mutant DHPS genotype corresponded to patients who had never received sulfa or sulfone prophylaxis, suggesting that DHPS mutants may be acquired de novo. There was no significant difference in favourable or adverse outcome in PCP caused by the wild or mutant DHPS genotypes (P = 0.34).

Detection of non-infectious conditions mimicking pneumonia in the intensive care setting: usefulness of bronchoalveolar fluid cytology

The present study investigated the usefulness of bronchoalveolar (BAL) fluid cytology in the identification of non-infectious pulmonary conditions in patients hospitalized in the intensive care unit (ICU) and suspected of pneumonia. A total of 182 BAL fluid samples obtained during a 27-month period from 130 ICU patients with suspected pneumonia were quantitatively cultured and investigated for opportunistic pathogens. Cytocentrifuged preparations stained with the May-Grünwald Giemsa and Perls's methods were reviewed. A non-infectious aetiology was considered when cultures yielded micro-organisms in quantities <10 3 colony-forming units (CFU) per ml, in the absence of any other pathogen and in conjunction with one or more of the following cytological findings: >20% haemosiderin macrophages, >10% lymphocytes, the presence of activated lymphocytes, plasma cells, >5% eosinophils, a preponderance of foamy macrophages, reactive type II pneumocytes or malignant cells. Patients' clinical records were reviewed to identify a clinical diagnosis for these episodes. In thirty-five (19·2%) BAL fluid samples from 26 patients, the cytological findings pointed to a non-infectious origin. An alternative diagnosis was ascertained in 20 of 26 patients. Diagnoses included: drug-induced pneumonitis ( n = 7), aspiration of gastric contents ( n = 2), pulmonary emboli ( n = 3), adult respiratory distress syndrome ( n = 4), lung contusion ( n = 1), cardiogenic pulmonary oedema ( n = 1), and carcinomatous lymphangitis ( n = 2). The BAL fluid cytological findings were readily discernable and proved to be useful in the diagnostic work-up of samples obtained from ICU patients with suspected pneumonia.